We are a family of four with two teenagers and I am wondering if the glow worm tour is worth doing for us? We are mindful of the cost. There seems to be two main operators - one more expensive than the other - Real journeys and NZ.com.

If anyone thinks the tour is worth doing can you recommend a tour operator and the best time of day to do this tour?

I have read that you can see the glow worms on a walk near Fox Glacier - does anyone know if this is right and whether this is just as good as the cave trip?

I've not taken the Te Anau glow worm tour, but from what I understand, most of the expense is for getting there and back via boat.

If you just want to see glow worms, minus the boat trip and the commentary, there are a free glow worm dells/grottos near Hokitika (after dark), Fox Glacier, HariHari (although I'm not clear on where exactly) and Punakaiki. You can also see them around Greymouth as part of a black water rafting tour.

Just saw your comment about Fox Glacier...

I don't remember if we've done this, but I have an area guide for Fox right in front of me which states "follow a delightful track opposite the BP garage on the main road in Fox Village". You may need to go at night, I don't know, but the tourist office could give you more details.

http://www.doc.govt.nz/footer-links/...-centres/#west

We did the glow worm cave tour at Te Anau several years ago with our kids/teens. We had seen the glow worm cave in Waitomo a couple years earlier, but we still enjoyed this tour. Our boat ride out to the island where the cave is located coincided with sunset, so the views on the way out were really nice. (If you do decide to do the tour, I would recommend going at this time, which was probably the 8:15pm tour since we were there in January. Not only do you get the nice sunset ride, but there were very few people there for the tour.)
I checked the websites that you mention and since they list the same tour times, that reinforces my recollection that there was only one operator for this tour. (At that time, I think the operator was called Fiordlands). Anyway, it would make sense to pay the lesser amount for the tickets since it should all be the same tour.
The U.S. dollar was much stronger when we were in NZ, so the cost of the tour was not so much for us. I'm not sure I would be willing to pay NZ 50.00 (or more) for this tour, especially since you might have the option to see glow worms for free. You probably won't see the huge numbers of glow worms that you might see at Te Anau, but you won't be spending huge amounts of money either.
Should you decide you want to do the trip, you could probably wait until you get to Te Anau to get tickets. I know that we were able to get same day tickets in January which is in the middle of the summer holiday season.
No matter what you decide, I would try to see the glow worms somewhere. They are magical to see and you are unlikely to experience them anywhere else.

Thanks very much to you both for the useful information. I think we will try and find the walk at Fox Glacier.

There'salso an easy glow worm walk at Franz Josef right on the main road right on the south end of town. We saw lots. Just remember your flashlight to find your way. Everyone in town should be able to tell you where.